64 research outputs found

    Quantum Aspects of Massive Gravity II: Non-Pauli-Fierz Theory

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    We investigate the non-Pauli-Fierz(nPF) theory, a linearized massive gravity with a generic graviton mass term, which has been ignored due to a ghost in its spectrum and the resultant loss of unitarity. We first show that it is possible to use the Lee-Wick mechanism, a unitarization through the decay of a ghost, in order to handle the sixth mode ghost of nPF, and then check for the quantum consistency. Once proven to be consistent, nPF could become a viable candidate for a large distance modification of gravity, because it naturally solves the intrinsic problems that most dark energy/modified gravity models suffer from: It smoothly converges to general relativity at short distances, and the small graviton mass necessary to modify gravity at large scales can be stable under the radiative corrections from the minimal gravity-to-matter coupling.Comment: 1+16pp, accepted for JHE

    On Non-Linear Actions for Massive Gravity

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    In this work we present a systematic construction of the potentially ghost-free non-linear massive gravity actions. The most general action can be regarded as a 2-parameter deformation of a minimal massive action. Further extensions vanish in 4 dimensions. The general mass term is constructed in terms of a "deformed" determinant from which this property can clearly be seen. In addition, our formulation identifies non-dynamical terms that appear in previous constructions and which do not contribute to the equations of motion. We elaborate on the formal structure of these theories as well as some of their implications.Comment: v3: 22 pages, minor comments added, version to appear in JHE

    Impact of Early Postnatal Androgen Exposure on Voice Development

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    Background: the impact of early postnatal androgen exposure on female laryngeal tissue may depend on certain characteristics of this exposure. We assessed the impact of the dose, duration, and timing of early androgen exposure on the vocal development of female subjects who had been treated for adrenocortical tumor (ACT) in childhood.Methods: the long-term effects of androgen exposure on the fundamental vocal frequency (F0), vocal pitch, and final height and the presence of virilizing signs were examined in 9 adult (age, 18.4 to 33.5 years) and 10 adolescent (13.6 to 17.8 years) female ACT patients. We also compared the current values with values obtained 0.9 years to 7.4 years after these subjects had undergone ACT surgery, a period during which they had shown normal androgen levels.Results: of the 19 subjects, 17 (89%) had been diagnosed with ACT before 4 years of age, 1 (5%) at 8.16 years, and 1 (5%) at 10.75 years. Androgen exposure (2 to 30 months) was sufficiently strong to cause pubic hair growth in all subjects and clitoromegaly in 74% (14/19) of the subjects, but did not reduce their height from the target value. Although androgen exposure induced a remarkable reduction in F0 (132 Hz) and moderate pitch virilization in 1 subject and partial F0 virilization, resulting in F0 of 165 and 169 Hz, in 2 subjects, the majority had normal F0 ranging from 189 to 245 Hz.Conclusions: Female laryngeal tissue is less sensitive to androgen exposure between birth and adrenarche than during other periods. Differential larynx sensitivity to androgen exposure in childhood and F0 irreversibility in adulthood are age-, concentration-, duration-, and timing-dependent events that may also be affected by exposure to inhibitory or stimulatory hormones. Further studies are required to better characterize each of these factors.Brazilian State of Parana Secretary of Science, Technology and Higher Education (SETI)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Raul Carneiro Hospital Association for Childhood Protection (AHPIRC)American Lebanese Syrian Associated Charities (ALSAC)SETIAHPIRCALSACInst Pesquisa Pele Pequeno Principe, Curitiba, Parana, BrazilHosp Pequeno Principe, Curitiba, Parana, BrazilFac Pequeno Principe, Curitiba, Parana, BrazilInst Voz Maringa, Maringa, Parana, BrazilUniversidade Federal de São Paulo, Dept Fonoaudiol, São Paulo, BrazilClin Voz, Curitiba, Parana, BrazilIrmandade Santa Casa Misericordia São Paulo, São Paulo, BrazilUniv Fed Parana, Dept Saude Comunitaria, BR-80060000 Curitiba, Parana, BrazilUniversidade Federal de São Paulo, Dept Fonoaudiol, São Paulo, BrazilWeb of Scienc

    Recomendações para o sistema de produção com poedeiras livres de gaiola para o Estado do Paraná.

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    Resumo: Este memorial descritivo para produção de ovos utilizando poedeiras livres de gaiola nasceu de uma experiencia a campo realizada através de um projeto da Embrapa em parceria com a Coopaf e Assesoar no Sudoeste do Paraná, com o objetivo de facilitar e proporcionar o contato dos agricultores com a avicultura diferenciada, seja ela colonial, caipira, capoeira e ou orgânica no Estado do Paraná. É uma ferramenta que se constitui em um modelo de produção para agricultura familiar com sustentabilidade, voltada principalmente para sistemas integrados e cooperativos. O sistema foi pensado de acordo com a diversidade de culturas e atividades, com ética, competência, respeito ao meio ambiente e como fonte extra de renda para o pequeno produtor. Com este diferencial, espera-se contribuir para que o produtor tenha motivação para sua permanência no meio rural. A adoção de uma avicultura diferenciada traz um modelo de produção que depende da consciência dos envolvidos, do mercado, do retorno ?nanceiro e da tomada de decisão no momento correto e de forma adequada. Não é uma receita rígida, mas sim uma proposta de produção que pode ser adaptada às realidades diversas das propriedades rurais familiares que queiram ofertar ovos diferenciados, em consonância com a legislação vigente no Estado do Paraná. Deste modo, as ideias aqui contidas servem para o produtor se inteirar, refletir sobre objetivos, perspectivas e efetividade da sua unidade produtiva familiar de ovos diferenciados

    "Plantar pro gasto": a importância do autoconsumo entre famílias de agricultores do Rio Grande do Sul.

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    O artigo discute a valoração e importância da produção para o autoconsumo na reprodução social das unidades familiares e caracteriza os alimentos autoconsumidos. Vale-se da pesquisa "Agricultura Familiar, Desenvolvimento Local e Pluriatividade" (UFRGS/UFPel/ CNPq-2003) que propiciou a formação de um banco de dados com informações sobre a dinâmica da agricultura familiar em quatro regiões distintas da geografia gaúcha, suas fontes e tipos de renda, entre estas o autoconsumo. Trazer este debate significa retomar um tema pouco discutido até então, e que, embora marginalizado ou considerado sem importância, desenvolve importante papel como renda não monetária, fortalece a segurança alimentar e adentra esferas da sociabilidade e identidade social. Além da introdução, apresenta-se o papel do autoconsumo na agricultura familiar, o cálculo da produção para o autoconsumo, discussão dos objetivos e resultados, e considerações finais. Os resultados demonstram que a produção para o autoconsumo é uma estratégia recorrente pelas unidades familiares e se diferencia de acordo com a dinâmica da agricultura familiar. Diferença esta expressa em valores relativos (%) e no número de estabelecimentos pertencentes a estratos diferenciados de autoconsumo, e pouco nos tipos de alimentos produzidos para este fim, observando-se uma homogeneidade dos hábitos alimentares

    ACTRIS ACSM intercomparison – Part 2: Intercomparison of ME-2 organic source apportionment results from 15 individual, co-located aerosol mass spectrometers

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    Chemically resolved atmospheric aerosol data sets from the largest intercomparison of the Aerodyne aerosol chemical speciation monitors (ACSMs) performed to date were collected at the French atmospheric supersite SIRTA. In total 13 quadrupole ACSMs (Q-ACSM) from the European ACTRIS ACSM network, one time-of-flight ACSM (ToF-ACSM), and one high-resolution ToF aerosol mass spectrometer (AMS) were operated in parallel for about 3 weeks in November and December~2013. Part 1 of this study reports on the accuracy and precision of the instruments for all the measured species. In this work we report on the intercomparison of organic components and the results from factor analysis source apportionment by positive matrix factorisation (PMF) utilising the multilinear engine 2 (ME-2). Except for the organic contribution of mass-to-charge ratio m/z 44 to the total organics (f44), which varied by factors between 0.6 and 1.3 compared to the mean, the peaks in the organic mass spectra were similar among instruments. The m/z 44 differences in the spectra resulted in a variable f44 in the source profiles extracted by ME-2, but had only a minor influence on the extracted mass contributions of the sources. The presented source apportionment yielded four factors for all 15 instruments: hydrocarbon-like organic aerosol (HOA), cooking-related organic aerosol (COA), biomass burning-related organic aerosol (BBOA) and secondary oxygenated organic aerosol (OOA). ME-2 boundary conditions (profile constraints) were optimised individually by means of correlation to external data in order to achieve equivalent / comparable solutions for all ACSM instruments and the results are discussed together with the investigation of the influence of alternative anchors (reference profiles). A comparison of the ME-2 source apportionment output of all 15 instruments resulted in relative standard deviations (SD) from the mean between 13.7 and 22.7 % of the source's average mass contribution depending on the factors (HOA: 14.3 ± 2.2 %, COA: 15.0 ± 3.4 %, OOA: 41.5 ± 5.7 %, BBOA: 29.3 ± 5.0 %). Factors which tend to be subject to minor factor mixing (in this case COA) have higher relative uncertainties than factors which are recognised more readily like the OOA. Averaged over all factors and instruments the relative first SD from the mean of a source extracted with ME-2 was 17.2 %.JRC.H.2-Air and Climat

    ACTRIS ACSM intercomparison – Part 1: Reproducibility of concentration and fragment results from 13 individual Quadrupole Aerosol Chemical Speciation Monitors (Q-ACSM) and consistency with co-located instruments

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    As part of the European ACTRIS project, the first large Quadrupole Aerosol Chemical Speciation Monitor (Q-ACSM) intercomparison study was conducted in the region of Paris for 3 weeks during the late-fall – early-winter period (November–December 2013). The first week was dedicated to the tuning and calibration of each instrument, whereas the second and third were dedicated to side-by-side comparison in ambient conditions with co-located instruments providing independent information on submicron aerosol optical, physical, and chemical properties. Near real-time measurements of the major chemical species (organic matter, sulfate, nitrate, ammonium, and chloride) in the non-refractory submicron aerosols (NR-PM1) were obtained here from 13 Q-ACSM. The results show that these instruments can produce highly comparable and robust measurements of the NR-PM1 total mass and its major components. Taking the median of the 13 Q-ACSM as a reference for this study, strong correlations (r2 > 0.9) were observed systematically for each individual Q-ACSM across all chemical families except for chloride for which three Q-ACSMs showing weak correlations partly due to the very low concentrations during the study. Reproducibility expanded uncertainties of Q-ACSM concentration measurements were determined using appropriate methodologies defined by the International Standard Organization (ISO 17025, 1999) and were found to be 9, 15, 19, 28, and 36 % for NR-PM1, nitrate, organic matter, sulfate, and ammonium, respectively. However, discrepancies were observed in the relative concentrations of the constituent mass fragments for each chemical component. In particular, significant differences were observed for the organic fragment at mass-to-charge ratio 44, which is a key parameter describing the oxidation state of organic aerosol. Following this first major intercomparison exercise of a large number of Q-ACSMs, detailed intercomparison results are presented, along with a discussion of some recommendations about best calibration practices, standardized data processing, and data treatment.JRC.H.2-Air and Climat
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